The electric field lines between a statically charged electrical conductor (O) and an earthed conductor (G), such as a central heating radiator.
Measuring static electricity
To measure static electric fields you need an electric field meter (also called a static meter or static locator). These tend to be on the expensive side, compared to EMF meters.
Electric fields have direction, like magnetic fields (see diagram above). Thus, readings can vary according to which way the meter is pointing. Also, if a statically charged surface rotates it will cause field strength changes nearby. What is more, the meter itself may affect the field, especially if it is earthed.
One meter, popular among ghost researchers, measures small changes in static electric fields. Unfortunately, it does not give the overall electric field so there is no way to know if it is unusual. Even more important, it does not say whether the field has gone up or down. It is very sensitive to small changes in the field, caused by people walking around, for instance. In some cases it is possible to detect someone walking in another room! For lots of technical info on static electricity see Mr Static!
© Maurice Townsend 2007
What is static electricity?
Static electricity, as the name implies, is electricity that does not move. By contrast, the electricity that we use to power all our appliances flows (hence 'electric current').
Static electricity is essentially a stationary electric field emanating from an object's surface which has electric charges on it. These electric charges arise from atoms on the surface gaining or losing electrons. An electric charge produces an electric field which can affect the surrounding environment (see later).
If the charged object is an electrical conductor, the charge will spread out over the whole surface. If the conductor is earthed then no charge will build up. If the object is an electrical insulator, then charge will accumulate on its surface, staying where it was created. This means that the charge, and so the field produced, will vary from point to point across the object. Charge can also reduce, without intervention, due to electrical conduction and the presence of air ions.
Effects of static electricity
The most familiar effect of a static electric field is the painful spark you get when you touch a door handle. This electric discharge happens when the electric field gradient between two objects reaches a level high enough for air to become a conductor. On a cold dry day if take off a hat your hair may 'stand on end' due to static electricity (though other things can cause this 'horripilation', such as cold and fear).
Static electricity can move objects! Don't get too excited, though. It can move bits of charged tissue paper around but nothing much heavier. That's because the limit for an electric field gradient before air starts to conduct (producing a spark) is very low.
It has been claimed that ghosts can produce static electric field changes. This is similar to the idea that ghosts produce magnetic field changes or produce an excess of negative air ions. In all these cases there seems little, if any, scientific, evidence to support the claims. Even the anecdotal evidence is difficult to track down.
This does not, of course, mean that there could not be a connection between static electric fields and the paranormal. A past ASSAP President, the late Michael Bentine, reported regularly smelling ozone (typically produced by electrical sparking) during seances. Whether this was associated with static electric fields or electrical equipment is not known. There are also one or two others isolated reports of apparent connections between static electric fields and paranormal events.
Causes of static electricity
The most common source of static electricity is an exchange of electrons between object surfaces. Bringing two surfaces into close contact and then separating them causes some electrons to move from one object to the other due to molecular attraction. The effect works better if the surfaces are rubbed together (triboelectrification). Many surfaces, particularly if they are electrically insulated, can easily produce static electricity.
Where is it found?
The short answer is that static electricity is found virtually everywhere, almost all the time (as anyone who deals with electronics at board level will know) but usually not at a level to be noticed without sensitive instruments.
Static builds up much less when the relative humidity exceeds about 60%. This is because moisture forms a layer on objects effectively neutralizing any charge there.
Causes of readings
Electric field meters will show charge changes due to charge accumulation (mostly triboelectrification), reduction (eg. through electrical conduction and air ions) and charged objects physically moving around. This means that charge will change a lot where there is object movement and even, to a lesser extent, when everything is stationary.
This last point is important to note because if you get a change in static field on a vigil when everything is motionless, it doesn't necessarily imply paranormal activity.
Using static electricity as an indicator for paranormal activity will always be problematic. It is too easy to produce static electricity unintentionally and predicting natural changes in the field is difficult.